1. Field of the Invention
This invention relates to interlocking containers. More specifically, this invention relates to interlocking containers especially useful for reusable ice pack substitutes.
2. Description of the Prior Art
Interlocking containers, such as stackable and nestable containers, etc., are known in the art as is shown, for example, in U.S. Design Pat. No. 205,196, Wikke, July 5, 1966; U.S. Pat. No. 353,600, Sloan, Nov. 30, 1886; U.S. Pat. No. 1,920,515, Marsden, Aug. 1, 1933; U.S. Pat. No. 2,974,841, Van Leer, Mar. 14, 1961; U.S. Pat. No. 3,131,829, Masser, May 5, 1964; U.S. Pat. No. 3,323,668, Hills, June 6, 1967; U.S. Pat. No. 3,255,607, Bair et al., June 14, 1966; U.S. Pat. No. 3,338,452, Oakley et al., Aug. 29, 1967; and U.S. Pat. No. 3,583,590, Ferraro, June 8, 1971. However, none of the patented containers are in any way similar to the containers of the present application.
Reusable ice pack substitutes, also known as refrigerating apparatus, are also known in the art as is shown in U.S. Pat. No. 1,716,551, Hayes et al., June 11, 1929; and French Pat. No. 1,031,675, published June 25, 1953. However, the Hayes et al. patent relates to a plurality of such containers permanently fastened together for the purpose of providing a flexible arrangement, whereas the French patent relates to a shape for such containers which permits easy and space saving stacking of a plurality of such containers, but does not provide for the interlocking of such containers.
Thus, there remains outstanding in the art a problem as follows: with reusable ice pack substitutes as they are presently made, manufacturers of the ice pack substitute must produce a plurality of different size packs to meet the requirements of different sectors of the market. The consumer, on the other hand, will require several packs of different sizes from time to time, to meet his own differing requirements.